/*
 Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
 

  The MySQL Connector/J is licensed under the terms of the GPLv2
  <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most MySQL Connectors.
  There are special exceptions to the terms and conditions of the GPLv2 as it is applied to
  this software, see the FLOSS License Exception
  <http://www.mysql.com/about/legal/licensing/foss-exception.html>.

  This program is free software; you can redistribute it and/or modify it under the terms
  of the GNU General Public License as published by the Free Software Foundation; version 2
  of the License.

  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU General Public License for more details.

  You should have received a copy of the GNU General Public License along with this
  program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth
  Floor, Boston, MA 02110-1301  USA



 */
package com.mysql.jdbc.log;

import java.util.Date;

import com.mysql.jdbc.Util;
import com.mysql.jdbc.profiler.ProfilerEvent;

/**
 * Provides logging facilities for those platforms that don't have built-in
 * facilities. Simply logs messages to STDERR.
 * 
 * @author Mark Matthews
 * 
 * @version $Id$
 */
public class StandardLogger implements Log {
	private static final int FATAL = 0;

	private static final int ERROR = 1;

	private static final int WARN = 2;

	private static final int INFO = 3;

	private static final int DEBUG = 4;

	private static final int TRACE = 5;

	public static StringBuffer bufferedLog = null;

	private boolean logLocationInfo = true;

	/**
	 * Creates a new StandardLogger object.
	 * 
	 * @param name
	 *            the name of the configuration to use -- ignored
	 */
	public StandardLogger(String name) {
		this(name, false);
	}

	public StandardLogger(String name, boolean logLocationInfo) {
		this.logLocationInfo = logLocationInfo;
	}

	public static void saveLogsToBuffer() {
		if (bufferedLog == null) {
			bufferedLog = new StringBuffer();
		}
	}

	/**
	 * @see com.mysql.jdbc.log.Log#isDebugEnabled()
	 */
	public boolean isDebugEnabled() {
		return true;
	}

	/**
	 * @see com.mysql.jdbc.log.Log#isErrorEnabled()
	 */
	public boolean isErrorEnabled() {
		return true;
	}

	/**
	 * @see com.mysql.jdbc.log.Log#isFatalEnabled()
	 */
	public boolean isFatalEnabled() {
		return true;
	}

	/**
	 * @see com.mysql.jdbc.log.Log#isInfoEnabled()
	 */
	public boolean isInfoEnabled() {
		return true;
	}

	/**
	 * @see com.mysql.jdbc.log.Log#isTraceEnabled()
	 */
	public boolean isTraceEnabled() {
		return true;
	}

	/**
	 * @see com.mysql.jdbc.log.Log#isWarnEnabled()
	 */
	public boolean isWarnEnabled() {
		return true;
	}

	/**
	 * Logs the given message instance using the 'debug' level
	 * 
	 * @param message
	 *            the message to log
	 */
	public void logDebug(Object message) {
		logInternal(DEBUG, message, null);
	}

	/**
	 * Logs the given message and Throwable at the 'debug' level.
	 * 
	 * @param message
	 *            the message to log
	 * @param exception
	 *            the throwable to log (may be null)
	 */
	public void logDebug(Object message, Throwable exception) {
		logInternal(DEBUG, message, exception);
	}

	/**
	 * Logs the given message instance using the 'error' level
	 * 
	 * @param message
	 *            the message to log
	 */
	public void logError(Object message) {
		logInternal(ERROR, message, null);
	}

	/**
	 * Logs the given message and Throwable at the 'error' level.
	 * 
	 * @param message
	 *            the message to log
	 * @param exception
	 *            the throwable to log (may be null)
	 */
	public void logError(Object message, Throwable exception) {
		logInternal(ERROR, message, exception);
	}

	/**
	 * Logs the given message instance using the 'fatal' level
	 * 
	 * @param message
	 *            the message to log
	 */
	public void logFatal(Object message) {
		logInternal(FATAL, message, null);
	}

	/**
	 * Logs the given message and Throwable at the 'fatal' level.
	 * 
	 * @param message
	 *            the message to log
	 * @param exception
	 *            the throwable to log (may be null)
	 */
	public void logFatal(Object message, Throwable exception) {
		logInternal(FATAL, message, exception);
	}

	/**
	 * Logs the given message instance using the 'info' level
	 * 
	 * @param message
	 *            the message to log
	 */
	public void logInfo(Object message) {
		logInternal(INFO, message, null);
	}

	/**
	 * Logs the given message and Throwable at the 'info' level.
	 * 
	 * @param message
	 *            the message to log
	 * @param exception
	 *            the throwable to log (may be null)
	 */
	public void logInfo(Object message, Throwable exception) {
		logInternal(INFO, message, exception);
	}

	/**
	 * Logs the given message instance using the 'trace' level
	 * 
	 * @param message
	 *            the message to log
	 */
	public void logTrace(Object message) {
		logInternal(TRACE, message, null);
	}

	/**
	 * Logs the given message and Throwable at the 'trace' level.
	 * 
	 * @param message
	 *            the message to log
	 * @param exception
	 *            the throwable to log (may be null)
	 */
	public void logTrace(Object message, Throwable exception) {
		logInternal(TRACE, message, exception);
	}

	/**
	 * Logs the given message instance using the 'warn' level
	 * 
	 * @param message
	 *            the message to log
	 */
	public void logWarn(Object message) {
		logInternal(WARN, message, null);
	}

	/**
	 * Logs the given message and Throwable at the 'warn' level.
	 * 
	 * @param message
	 *            the message to log
	 * @param exception
	 *            the throwable to log (may be null)
	 */
	public void logWarn(Object message, Throwable exception) {
		logInternal(WARN, message, exception);
	}

	private void logInternal(int level, Object msg, Throwable exception) {
		StringBuffer msgBuf = new StringBuffer();
		msgBuf.append(new Date().toString());
		msgBuf.append(" ");

		switch (level) {
		case FATAL:
			msgBuf.append("FATAL: ");

			break;

		case ERROR:
			msgBuf.append("ERROR: ");

			break;

		case WARN:
			msgBuf.append("WARN: ");

			break;

		case INFO:
			msgBuf.append("INFO: ");

			break;

		case DEBUG:
			msgBuf.append("DEBUG: ");

			break;

		case TRACE:
			msgBuf.append("TRACE: ");

			break;
		}

		if (msg instanceof ProfilerEvent) {
			msgBuf.append(LogUtils.expandProfilerEventIfNecessary(msg));

		} else {
			if (this.logLocationInfo && level != TRACE) {
				Throwable locationException = new Throwable();
				msgBuf.append(LogUtils
						.findCallingClassAndMethod(locationException));
				msgBuf.append(" ");
			}
			
			if (msg != null) {
				msgBuf.append(String.valueOf(msg));
			}
		}

		if (exception != null) {
			msgBuf.append("\n");
			msgBuf.append("\n");
			msgBuf.append("EXCEPTION STACK TRACE:");
			msgBuf.append("\n");
			msgBuf.append("\n");
			msgBuf.append(Util.stackTraceToString(exception));
		}

		String messageAsString = msgBuf.toString();

		System.err.println(messageAsString);

		if (bufferedLog != null) {
			bufferedLog.append(messageAsString);
		}
	}
}
